Goodwill and Intangible Assets Goodwill Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Goodwill [Line Items]
Goodwill Impairment	$ 0	$ 167
Goodwill, Impaired, Accumulated Impairment Loss	$ 239
Eastern Hemisphere
Goodwill [Line Items]
Goodwill Impairment		$ (167)

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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